Storm Water Diversion System Deals With Drought, Downpour

Two California aviation facilities faced different storm water runoff challenges. During infrequent rain events, the manual valve in the San Diego Airport's diversion system might not be tested as often as needed. In heavy downpours, Miramar Naval Air Station's sanitary sewers risked being overwhelmed. The Attitude Technology Automatic Storm water Diversion System (ASWDS) from C.I.Agent Storm•Water Solutions efficiently solved both problems.

In San Diego, the existing water diversion system in the trash collection area on the tarmac could not be relied on to divert water from the sanitary sewer to the storm water sewer. The new ASWDS system employs an automatic STORMDiverter valve actuated by the STORMController. When 1/10 in. of rain falls within 2 hr, a signal is sent from the STORMSwitch to close the valve, redirecting rainwater to the storm sewer.

But during months with little rain, manual valves were at risk to be left uncycled and potentially non-operational. Now, the ASWDS automatically senses when rain hasn't fallen for seven days and automatically exercises the valve to ensure reliability.

Miramar Naval Air Station installed its first ASWDS in the C-130 wash area in 2006. Because of its success and low maintenance, a second system was recently installed in the new Helicopter and Osprey wash area to ensure compliance during heavy rain events.

Each ASWDS is pre-configured for site-specific needs and can be further programmed as parameters change. For the Miramar project, the customer wanted an override installed in case helicopters needed to be washed in the rain. C.I.Agent Storm•Water Solutions personnel worked with the supplier of the Hydroblaster washing system, Hydro Engineering, to coordinate with the ASWDS.

If the Hydroblaster activates during a rain event, a current sensor overrides the rain gauge signal and closes access to the storm sewer. This prevents a non-compliant storm water discharge.

A key feature of the ASWDS is the IP68-rated submersible actuator. While other systems are designed to keep the actuator above water, this is a common failure point as water often gets to the actuator unintentionally. The ASWDS actuator functions in up to 10 ft of water.

As with the San Diego Airport system, another benefit at Miramar is the automatic exercising of valves. The controller fully opens and closes the valves every seven days when long periods pass without cycling.